Determine why or if a chandelier is really needed. Chandeliers can impart important information about the scene, but there are two things that make chandeliers difficult to manage, regardless of design--engineering how the chandelier will be safely "flown" over the stage, and dealing with the annoying shadows that a chandelier will cast. It's also important to remember that if a chandelier must really produce light, you will have to grapple with additional issues, such as very long and unsightly power cords trailing up into the fly loft, and electrical safety. Unless there is a critical reason why a chandelier must appear on the set, you should reconsider the need to add a chandelier to the set dressings. You might also want to reconsider the piece if you do not have a fly system over the stage.
Establish the period look of the chandelier. Chandelier designs can vary widely, from crude wooden designs from the Middle Ages to highly decorated and gilded pieces from Victorian times, all the way to modern designs of the present day. You'll want to choose a look that is appropriate for your play's time period.
Seek to Modify first--build last. Once you have your design in mind, save yourself time and money by seeking to modify an existing chandelier, purchased at a home improvement store or flea market, into a more appropriate period piece. This is especially true if the chandelier must really work. It's much faster to change the look of a real chandelier than to build one from scratch. It's even faster to borrow or rent a completed period set piece from another theater organization or a props shop.
Pare down the design to the essentials. Because a chandelier must be flown overhead, reducing the weight of the piece is important. If you are building the chandelier, and it does not have to produce light, try to use the lightest materials possible such as papier-mâché, urethane foam or PVC piping. Avoid using heavy materials, such as wood and metal pipes. Reduce the design characteristics to the bare minimum needed to "sell" the idea of a "chandelier" to the audience's eye. Achieve the overall look of a chandelier that "reads" from the middle of the audience seating section, and then stop. Don't add more weight, work, or time than the effect is worth.